Trinity Aquiferinteractive map | cross-section

Summary

The Trinity Aquifer, a major aquifer, extends across much of the central and northeastern part of the state. It is composed of several smaller aquifers contained within the Trinity Group. Although referred to differently in different parts of the state, they include the Antlers, Glen Rose, Paluxy, Twin Mountains, Travis Peak, Hensell, and Hosston aquifers. These aquifers consist of limestones, sands, clays, gravels, and conglomerates. Their combined freshwater saturated thickness averages about 600 feet in North Texas and about 1,900 feet in Central Texas.

In general, groundwater is fresh but very hard in the outcrop of the aquifer. Total dissolved solids increase from less than 1,000 milligrams per liter in the east and southeast to between 1,000 and 5,000 milligrams per liter, or slightly to moderately saline, as the depth to the aquifer increases. Sulfate and chloride concentrations also tend to increase with depth.

The aquifer is one of the most extensive and highly used groundwater resources in Texas. Although its primary use is for municipalities, it is also used for irrigation, livestock, and other domestic purposes. Some of the state's largest water level declines, ranging from 350 to more than 1,000 feet, have occurred in counties along the IH-35 corridor from McLennan County to Grayson County. These declines are primarily attributed to municipal pumping, but they have slowed over the past decade as a result of increasing reliance on surface water.

Reports

ID Date Type Description
AA09-07 11/22/2010 Aquifer assessment Reevaluation of desired future conditions for the Trinity Aquifer in Comanche and Erath counties
GMA9_DFC_02 7/26/2010 DFC submission Desired future conditions for the Edwards Group of the Edwards-Trinity (Plateau) and Trinity aquifers
GMA8_DFC_03 9/17/2008 DFC submission Desired future conditions for the Trinity Aquifer
GMA10_DFC_03 8/23/2010 DFC submission Desired future conditions for the Trinity, Austin Chalk, Buda Limestone, and Leona Gravel aquifers
B-6310 12/1/1973 Groundwater bulletin Reconnaissance Investigation of the Ground-Water Resources of the Brazos River Basin, Texas
B-6212 7/1/1962 Groundwater bulletin Geology and Ground-Water Resources of Uvalde County, Texas
B-5911 10/1/1959 Groundwater bulletin Ground-Water Geology of Bexar County, Texas
R-019 3/1/1966 TWDB numbered report Ground-Water Resources of Guadalupe County, Texas
R-350 11/1/1999 TWDB numbered report Changes in Groundwater Conditions in the Edwards and Trinity Aquifers, 1987-1997, for Portions of Bastrop, Bell, Burnet, Lee, Milam, Travis, and Williamson Counties, Texas
R-109 3/1/1970 TWDB numbered report Ground-Water Resources of Bastrop County, Texas
R-160 11/1/1972 TWDB numbered report Ground-Water Resources of Navarro County, Texas
B-5601 8/1/1956 Groundwater bulletin Geology and Ground-Water Resources of Medina County, Texas
B-6004 8/1/1960 Groundwater bulletin Geology and Ground-Water Resources of Hays County, Texas
B-6210 5/1/1962 Groundwater bulletin Ground-Water Geology of Bandera County, Texas
R-046 5/1/1967 TWDB numbered report Occurrence and Quality of Ground Water in Brown County, Texas
R-058 8/1/1967 TWDB numbered report Occurrence and Quality of Ground Water in Montague County, Texas
R-235 7/1/1979 TWDB numbered report Occurrence, Availability, and Chemical Quality of Ground Water in the Edwards Plateau Region of Texas
R-322 3/1/1990 TWDB numbered report Ground-Water Evaluation in and Adjacent to Dripping Springs, Texas
R-276 6/1/1983 TWDB numbered report Occurrence, Availability, and Quality of Ground Water in Travis County, Texas
R-102 11/1/1969 TWDB numbered report Ground-Water Resources of Kerr County, Texas
R-174 7/1/1973 TWDB numbered report Ground-Water Resources of Blanco County, Texas
R-029 9/1/1966 TWDB numbered report Base-Flow Studies, Upper Guadalupe River Basin, Texas, Quality and Quantity
R-273 1/1/1983 TWDB numbered report Ground-Water Availability of the Lower Cretaceous Formations in the Hill Country of South-Central Texas
R-353 9/1/2000 TWDB numbered report Groundwater Availability of the Trinity Aquifer, Hill Country Area, Texas: Numerical Simulations through 2050
R-224 10/1/1978 TWDB numbered report Occurrence, Quantity, and Quality of Ground Water in Taylor County, Texas
R-331 7/1/1991 TWDB numbered report Ground-Water Quality Monitoring of the Trinity Aquifer in the Vicinity of Erath County
R-269 4/1/1982 TWDB numbered report Occurrence, Availability and Chemical Quality of Ground Water in the Cretaceous Aquifers of North-Central Texas, Volumes 1 & 2
R-195 11/1/1975 TWDB numbered report Ground-Water Resources of Part of Central Texas with Emphasis on the Antlers and Travis Peak Formations, Volumes 1 & 2
R-319 1/1/1990 TWDB numbered report Evaluation of Water Resources in Part of Central Texas
R-346 3/1/1996 TWDB numbered report The Paleozoic and Related Aquifers of Central Texas
R-339 8/1/1992 TWDB numbered report Evaluation of Ground-Water Resources of the Paleozoic and Cretaceous Aquifers in the Hill Country of Central Texas
R-349 11/1/1999 TWDB numbered report Updated Evaluation of Water Resources in Part of North-Central Texas, 1990-1999
R-318 1/1/1990 TWDB numbered report Evaluation of Water Resources in Part of North-Central Texas
R-308 8/1/1988 TWDB numbered report Occurrence and Quality of Ground Water in Jack County, Texas
R-377 6/1/2011 TWDB numbered report Groundwater Availability Model: Hill Country Portion of the Trinity Aquifer of Texas
AA09-02_D 4/20/2010 Aquifer assessment Desired future condition scenarios for the middle and lower Trinity Aquifer in Groundwater Management Area 10
AA10-03_D 6/10/2010 Aquifer assessment Desired future condition scenarios for the Trinity Aquifer in Groundwater Management Area 10
AA10-06 7/28/2010 Aquifer assessment Desired future condition scenarios for the Trinity Aquifer in Groundwater Management Area 10
GR11-004_MP 9/26/2011 GAM run - Management Plan Management plan information for Prairielands GCD
GR10-066_MP 1/19/2011 GAM run - Management Plan Management plan information for Central Texas GCD
GR10-034_MP 10/26/2010 GAM run - Management Plan Management plan information for North Texas GCD
GR10-032_MP 9/29/2010 GAM run - Management Plan Management plan information for Red River GCD
GR10-029_MP 1/4/2011 GAM run - Management Plan Management plan information for Post Oak Savannah GCD
GT10-005 9/3/2010 GAM task Predictive simulations for the Trinity Aquifer in Groundwater Management Area 9
GT10-031 1/25/2011 GAM task Additional results from the analysis completed in GAM Task 10-005
GR10-014_MP 6/9/2010 GAM run - Management Plan Management plan information for Lost Pines GCD
GR10-009_MP 6/9/2010 GAM run - Management Plan Management plan information for Clearwater UWCD
GR10-004_MP 4/15/2010 GAM run - Management Plan Management plan information for Middle Trinity GCD
GR09-033_MP 7/29/2010 GAM run - Management Plan Management plan information for Hays Trinity GCD
GR09-032_MP 7/9/2010 GAM run - Management Plan Management plan information for Trinity-Glen Rose GCD
GR09-031_MP 7/9/2010 GAM run - Management Plan Management plan information for Medina County GCD
GR09-030_MP 10/21/2009 GAM run - Management Plan Management plan information for Cow Creek GCD
GR09-011 9/14/2010 GAM run Predictive simulations for the Edwards-Trinity (Plateau) and Trinity aquifers in Groundwater Management Area 9
GR09-012 9/14/2010 GAM run Predictive simulations for the Edwards-Trinity (Plateau) and Trinity aquifers in Groundwater Management Area 9
GR09-024 9/14/2010 GAM run Predictive simulations for the Edwards-Trinity (Plateau) and Trinity aquifers in Groundwater Management Area 9
GR09-011_S 9/13/2010 GAM run Predictive simulations for the Edwards-Trinity (Plateau) and Trinity aquifers in Groundwater Management Area 9
GR09-012_S 9/13/2010 GAM run Predictive simulations for the Edwards-Trinity (Plateau) and Trinity aquifers in Groundwater Management Area 9
GR09-024_S 9/13/2010 GAM run Predictive simulations for the Edwards-Trinity (Plateau) and Trinity aquifers in Groundwater Management Area 9
GR09-022_MP 11/20/2009 GAM run - Management Plan Management plan information for Upper Trinity GCD
GR09-021_MP 7/31/2009 GAM run - Management Plan Management plan information for Neches & Trinity Valleys GCD
GR08-089_MP 5/20/2009 GAM run - Management Plan Management plan information for Lost Pines GCD
GR08-083 5/17/2010 GAM run Additional results from the analysis completed in GAM Run 08-064
GR08-072_MP 10/3/2008 GAM run - Management Plan Management plan information for Middle Trinity GCD
GR08-071_MP 10/3/2008 GAM run - Management Plan Management plan information for Neches & Trinity Valleys GCD
GR08-070 12/2/2008 GAM run Predictive and steady-state simulations for the Trinity Aquifer in Groundwater Management Area 9
GR08-069_MP 9/10/2008 GAM run - Management Plan Management plan information for McLennan County GCD
GR08-066 5/17/2010 GAM run Predictive simulation for the Woodbine and Trinity aquifers in Groundwater Management Area 8
GR08-065_MP 8/22/2008 GAM run - Management Plan Management plan information for Northern Trinity GCD
GR08-064 5/17/2010 GAM run Predictive simulation for the Woodbine and Trinity aquifers in Groundwater Management Area 8
GR08-053_MP 8/1/2008 GAM run - Management Plan Management plan information for Fox Crossing Water District
GR08-040_MP 5/30/2008 GAM run - Management Plan Management plan information for Saratoga UWCD
GR08-030 8/19/2008 GAM run Predictive simulation for the Trinity Aquifer in Groundwater Management Area 9
GR08-020 7/28/2008 GAM run Predictive simulation for the Trinity Aquifer in Groundwater Management Area 9
GR08-015 7/8/2008 GAM run Predictive simulation for the Trinity Aquifer in Groundwater Management Area 9
GR08-005 2/11/2008 GAM run Predictive simulations for the Trinity Aquifer in Groundwater Management Area 8
GR08-006 2/11/2008 GAM run Predictive simulations for the Trinity Aquifer in Groundwater Management Area 8
GMA8_DFC_05 4/27/2011 DFC submission Desired future conditions for the Blossom, Brazos River Alluvium, Edwards (Balcones Fault Zone), Ellenburger-San Saba, Hickory, Marble Falls, Nacatoch, Trinity, and Woodbine aquifers
GR07-030 10/26/2007 GAM run Predictive simulations for the Trinity Aquifer in Groundwater Management Area 8
GR07-024_MP 9/5/2007 GAM run - Management Plan Management plan information for Cow Creek GCD
GR07-018 7/13/2007 GAM run Simulation to document locations and discharges to springs and rivers, and document the water budget in Groundwater Management Area 9
GR07-009 6/29/2007 GAM run Predictive simulation for the Trinity Aquifer in Groundwater Management Area 8
GR06-012 7/31/2006 GAM run Predictive simulation for the Trinity Aquifer in Lampasas County (Saratoga UWCD)
GR05-039 1/3/2006 GAM run Predictive simulation for the Trinity Aquifer in Mills County
GR05-035 9/12/2005 GAM run Effects on Guadalupe River flow from various pumping scenarios in the Trinity Aquifer
GR05-030 7/15/2005 GAM run Recharge information for the Carrizo-Wilcox, Edwards-Trinity (Plateau) and Trinity aquifers in Uvalde County
GR05-031 7/21/2005 GAM run Recharge information for the Carrizo-Wilcox and Trinity aquifers in Medina County
GR04-018 10/7/2004 GAM run Recharge rates for the Trinity Aquifer in Hays Trinity GCD
GR04-006 5/6/2004 GAM run Analytical groundwater modeling to estimate water level drawdown in Erath and Comanche counties
GR03-034 5/14/2004 GAM run Analytical groundwater modeling to assess water level drawdown by implementing hypothetical well fields
GR03-029 10/31/2003 GAM run Decadal water level declines for the Upper and Middle Trinity aquifers of the Trinity (Hill Country) GAM
GR03-025 9/2/2003 GAM run Recharge, leakage, and total storage for the Trinity (Hill Country) in Bandera County River Authority and GCD
GR03-012 7/18/2003 GAM run Water budget, storage, and drawdown in 2050 for the Trinity (Hill Country) and Carrizo-Wilcox aquifers in Medina County GCD
GR03-011 3/21/2003 GAM run Water budget by county for the Trinity (Hill Country) Aquifer
GR03-005 5/20/2003 GAM run Estimated water levels at specified locations in the Trinity (Hill Country) GAM
GR03-002 3/21/2003 GAM run Average well yield in Kendall County for the Trinity (Hill Country) Aquifer GAM
GR08-084_MAG 3/5/2009 GAM run - MAG Managed available groundwater estimates for the Trinity Aquifer in Groundwater Management Area 8
GR11-008 1/27/2012 GAM run Trinity Aquifer model runs for Central Texas GCD
GR11-005 1/26/2012 GAM run Trinity Aquifer model runs for Central Texas GCD
GR02-001 3/21/2003 GAM run County water budget for the Trinity (Hill Country) Aquifer GAM
GR02-002 3/21/2003 GAM run County water budget for the Trinity (Hill Country) Aquifer GAM
GR10-063_MAG 12/14/2011 GAM run - MAG Modeled available groundwater estimates for the Trinity Aquifer in Groundwater Management Area 8
GR10-050_MAG_Rev1 3/30/2012 GAM run - MAG Modeled available groundwater estimates for the Trinity Aquifer in Groundwater Management Area 9
GR11-006 2/2/2012 GAM run Predictive simulations for the Trinity Aquifer in Clearwater UWCD
AA10-29_MAG 11/29/2011 Aquifer assessment MAG Modeled available groundwater for the Trinity Aquifer in Groundwater Management Area 10
CR-1004831116 7/11/2012 Contract report Aquifer Test and Related Well Information from Public Water Supply Wells in Groundwater Management Area 8
R-380 7/1/2011 TWDB numbered report Aquifers of Texas
GR12-021_MP 9/4/2012 GAM run - Management Plan Management plan data for Headwaters GCD
GR12-015_MP 9/4/2012 GAM run - Management Plan Management plan data for Hill Country UWCD
CR-1004831114 8/9/2012 Contract report Ground Water Recharge Model: Calibration and Validation for Remotely-Sensed Dual Coefficient (RDC) GMA8 ET Estimation
GR10-043_MAG_Rev1 11/12/2012 GAM run - MAG Modeled available groundwater for the Edwards-Trinity (Plateau), Pecos Valley, and Trinity aquifers in Groundwater Management Area 7
GR08-011_MP 4/29/2008 GAM run - Management Plan Management plan information for Blanco-Pedernales GCD
GR13-001_MP 1/24/2013 GAM run - Management Plan Management plan data for Blanco-Pedernales GCD
GR13-013_MP 7/3/2013 GAM run - Management Plan Management plan data for Neches & Trinity Valleys GCD
GR13-019_MP 7/3/2013 GAM run - Management Plan Management Plan data for Saratoga UWCD
GR13-016_MP 8/7/2013 GAM run - Management Plan Management plan data for Middle Trinity GCD
GT13-029_TERS 9/19/2013 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 6
GT13-030_TERS 10/2/2013 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 7
GT13-032_TERS 10/2/2013 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 9
GT13-033_TERS 8/20/2013 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 10
GT13-036_TERS_Ver2 7/15/2013 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 13
GR13-029_MP 11/15/2013 GAM run - Management Plan Management plan data forCow Creek GCD
GR13-023_MP 12/18/2013 GAM run - Management Plan Management plan information for Real-Edwards Conservation and Reclamation District
GT13-031_TERS 1/15/2014 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 8
GT13-034_TERS 4/2/2014 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 11
GT13-035_TERS_Ver2 5/16/2014 GAM task - Total Estimated Recoverable Storage Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 12
No Result